The approach interpreting lifestyles as principally styles of thought has its roots in the soil of psychological analysis. Initially, starting with Alfred Adler, a lifestyle was understood as a style of personality, in the sense that the framework of guiding values and principles which individuals develop in the first years of life end up defining a system of judgement which informs their actions throughout their lives. Later, particularly in Milton Rokeach's work, Arnold Mitchell's VALS research and Lynn R. Kahle's LOV research, lifestyles' analysis developed as profiles of values, reaching the hypothesis that it is possible to identify various models of scales of values organized hierarchically, to which different population sectors correspond. Then with Daniel Yankelovich and William Wells we move on to the so-called AIO approach in which attitudes, interests and opinions are considered as fundamental lifestyles' components, being analysed from both synchronic and diachronic points of view and interpreted on the basis of socio-cultural trends in a given social context (as, for instance, in Bernard Cathelat's work). Finally, a further development leads to the so-called profiles-and-trends approach, at the core of which is an analysis of the relations between mental and behavioural variables, bearing in mind that socio-cultural trends influence both the diffusion of various lifestyles within a population and the emerging of different modalities of interaction between thought and action.
